helpmidas: command not found

Have You tried accessing the binary with the full path?

Maybe Your $PATH variable doesn't contain the default paths? echo $PATH should give something like:

[root@server ~]# echo $PATH
/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin

If it's empty, You may set the PATH variable with this command

export PATH="/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin"

On Debian possible default full paths are:

/usr/bin/helpmidas - from package: eso-midas

You may install the required package with command apt-get install {package}
Error in other languages:
helpmidas: bevel nie gevind nie
helpmidas: comandă negăsită
helpmidas: comando não encontrado
helpmidas: commande introuvable
helpmidas: command not found
helpmidas: käsku ei ole
helpmidas: không tìm thấy lệnh
helpmidas: komanda nerasta
helpmidas: Kommando nicht gefunden.
helpmidas: kommandot finns inte
helpmidas: komut yok
helpmidas: nie znaleziono polecenia
helpmidas: níor aimsíodh an t-ordú
helpmidas: no se encontró la orden
helpmidas: no s'ha trobat l'ordre
helpmidas: opdracht niet gevonden
helpmidas: parancs nem található
helpmidas: perintah tidak ditemukan
helpmidas: príkaz nenájdený
helpmidas: příkaz nenalezen
helpmidas: команда не найдена
helpmidas: командата не е открита
helpmidas: 命令找不到
helpmidas: コマンドが見つかりません